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§13.10. Defining new prepositions

The term preposition is used here, a little loosely, to mean anything which we add to the verb to be in order to talk about some relation or other. We have seen many examples already, such as:

To be in - The ball is in the box.
To be part of - The lever is part of the slot machine.

These are defined just the way verbs are. Compare the following:

Suspicion relates various people to one person.

The verb to suspect means the suspicion relation.

The verb to be suspicious of means the suspicion relation.

The result of this is that

Hercule Poirot suspects Colonel Hotchkiss.
Hercule Poirot is suspicious of Colonel Hotchkiss.

are exactly equivalent, and so are these two descriptions:

somebody who suspects Colonel Hotchkiss
somebody suspicious of Colonel Hotchkiss

While most prepositions are short ("in", "part of", "suspicious of"), they're free to be longer if need be ("inordinately far away from"): the limit is 30 words, which should be ample.

We can also define verbs as auxiliaries, like so:

The verb to be able to approach means the approachability relation.

Now we can ask if Poirot "can approach" Hotchkiss, and so on.

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*ExampleThe Abolition of Love
A thorough exploration of all the kinds of relations established so far, with the syntax to set and unset them.

*ExampleSwerve left? Swerve right? Or think about it and die?
Building a marble chute track in which a dropped marble will automatically roll downhill.

*ExampleBeneath the Surface
An "underlying" relation which adds to the world model the idea of objects hidden under other objects.

Clothing for the player that layers, so that items cannot be taken off in the wrong order, and the player's inventory lists only the clothing that is currently visible.